dangerous

The term “just enough knowledge to be dangerous” comes immediately to mind with this one. The official description is “a large scale pan and tilt propane Flame Effect” but that hardly does this thing justice. The Anti-Sanecraft ARTillery Cannon is a three-barrel fire cannon that can move around like its namesake and launch massive propane bursts from two 1″ diameter barrels. The third barrel is somewhat special, it is constructed of stronger steel and can be pre-fed with oxygen to create one massive intense propane-O2 mixed fire burst.

The trick about the whole thing is that when oxygen and propane are mixed it is a highly volatile and dangerous thing, in a closed space they classify as an explosive. Instead oxygen is filled directly into the open ended barrel separately and is allowed to sit until propane fires it out. This mixes the two fuels in the open air where it is safer and far away from any bystanders. We would not suggest you try this at all ever, as the effect was so loud during the Transformus festival that neighbors, miles away from the large festival ground, were complaining about rattling windows. This is the kind of place where several thousand watt sound systems are pushed near the red with no issue, just to give a bit of a comparison.

We can’t seem to find a video of this thing in action either [Beyond Joy] just posted a video of this crazy contraption in action (without the O2 effect), check it out after the jump! Don’t forget to check the facebook photo album for all the NPT pipe fitting action, (warning some images of the phallic controls are very mildly NSFW).

Hackaday headquarters has recently been overrun by techno-groupies hanging around outside so we decided to take some measures to discourage that. A word of warning though, if last week’s video ruffled your feathers then you probably shouldn’t watch this one. In this video [Jack] shows you how to create a stun glove using a disposable camera and some leather spikes. To prove that it really works, he intentionally takes a jolt from it courtesy of Hackaday’s security chief [Vlad].

The gentleman you see in the image above is [Jörg Sprave] of The Slingshot Channel. He is a self-proclaimed “Supid Expert” on the subject of slingshots and has taken his love of flinging things at absurd velocities to a whole new level.

His latest creation is a machete slingshot, which is really more accurately described as a machete crossbow. Measuring over six feet long, the impressive apparatus fires a specially altered machete with an insane amount of force using thick rubber bands. In the test firing shown in the video below, the machete is embedded up to the hilt in six layers of very thick cardboard, requiring quite a bit of work to remove.

As he states in the video while brandishing his bloodied forearm, building such a device is extremely dangerous, and should be limited to “Stupid Experts” . In no way should you attempt to build one of your own.

The concept of a HERF gun is not incredibly complex. Much like your microwave at home functions, a high voltage power source is used to drive a magnetron, which produces micro wave radiation at 2.45GHz. These waves are then guided away from the magnetron using a waveguide, towards whatever the target might be. These waves then energize the target in a similar fashion as the water molecules in your food are energized during cooking.

[Jimmy] has not quite finished his HERF gun as he still needs to build a waveguide for it and then safely mount it for use. In the meantime, check out the pair of HERF guns we found in the videos below.

As a parting note, we must stress that building a similar device is dangerous, very dangerous – especially if you do not know what you are doing. Microwaves contain high voltage components, and exposure to microwave radiation can be deadly under certain circumstances. Stay safe!

Ok, we’ll start this off by saying, looking at lasers can damage your eyes. Be careful. Now that we’ve got that absolutely clear, we couldn’t help but find this super quick and dirty laser microscope fascinating. Basically, they are just pointing a laser through a drop of water suspended from the tip of a syringe. The image of the contents of the drop are projected on a nearby wall. The drop seen in the video after the break was taken from a potted plant and you can see all kinds of life squirming around in there. Just don’t try it with this laser.

[Kirov], a regular reader and one of our most notorious commenters, tipped us off about this lawn mowing hack. On one hand we’re wary that this is bait for a huge flame war, but on the other hand it’s a hack that brings a smile to our mischievous faces. By pounding a stake into the center of the yard and connecting a mower to it with a piece of rope, [Korey99] has achieve an automated lawn mower. He tied the self-propelled mower’s throttle bar down to make the machine run unattended. There’s no kill switch or any kind of remote control for the lawn mower so we wonder what happens when the rope gets all wound up?

Sometime the projects you see at the local hacker space are better left a secret when you return home for the evening. Case in point, this ping-pong ball launcher that can put holes in a sheet of OSB. The projectile is made more lethal because the ball has been injected with water to dramatically increase the density. Compressed air is used to propel it from the 14 round magazine with devastating effect.